In air suspension systems for motor vehicles, there is the aim in some applications for it to be possible to set the properties of the air suspension system in a manner which is as simple as possible. An air suspension system has an air spring strut with a multiplicity of different components which have an effect on the properties of the air suspension system, for example the size or the material of an air spring pot or a rolling bellows which rolls on a rolling tube during compression and during rebound, or the configuration of a valve, in particular a pressure holding valve for determining the pressure in a pressure space of the air spring strut which is formed in the air spring pot and which is delimited movably by the rolling bellows. Here, an inflow or outflow of air into or out of the pressure space can be regulated via the valve. Here, the properties of the air spring system can also be set by way of a head bearing which is arranged in the air spring strut, in particular by way of a mechanical prestress which is exerted on the head bearing. A prestress of this type can be set by means of the arrangement of the valve device in the air spring strut in contact with the head bearing. The valve device can be brought into contact, for example, with the head bearing under prestress, in order to exert a force in the axial direction, that is to say in the direction of a center longitudinal axis of the air spring strut or head bearing, on the head bearing. Here, a pilot pressure can be exerted on an elastic part of the head bearing, by an underside of a housing of the valve device being brought into contact with the elastic part. Here, the valve device is seated above the head bearing in the air spring strut and comprises a valve unit which is received in a housing and via which the pressure in a pressure space of the air spring strut can be held, the housing being in contact with the head bearing.
Here, known housings are configured, for example, from a material which is designed for great surface pressures, for example formed as a metallic cast part, in particular made from aluminum.
Patent document DE 198 54 540 C2 describes a pressure holding valve for air suspension systems, in which pressure holding valve a valve member in the form of a diaphragm is arranged in a housing.
Laid-open specification DE 102 25 354 A1 describes a head bearing of a motor vehicle spring strut.